Valve structure for pressurized liquid dispenser

Claim 1

In a dispenser that automatically discharges metered quantities of a pressurized liquid from a container at timed intervals, said dispenser of the type that includes a body assembly that defines an elongate vertical liquid metering chamber having first and second ends, an elongate armature of less length than said metering chamber movably disposed in the latter, said armature formed from a magnetically attractable material and having first and second ends, said armature of less transverse cross section than that of said metering chamber, a spray nozzle, first passage means in communication with said spray nozzle, a solenoid surrounding at least a portion of said metering chamber, a source of electric power, second passage means that maintain communication between the interior of said container and a tubular valve seat that extends into said metering chamber from said second end thereof, a normally open electric circuit means connected to said solenoid and said source of power that periodically close to momentarily energize said solenoid to move said armature from a first to a second position, first valve means on said second end of said armature that seal witH said tubular valve seat when said armature is in said second position, an improved valve structure for maintaining said liquid in said metering chamber when said armature is in said first position, said valve structure including: a. a tapered rigid element of circular transverse cross section that projects outwardly from the center of said first end of said armature; b. a resilient first ring snuggly and sealingly disposed in a recess formed in said first end of said metering chamber, said first ring having a centrally disposed opening therein coaxially aligned with said element, said recess in communication with said first passage means, with said element when said armature is in said first position extending into said opening to pressure seal with said ring and exert an outward radially directed force thereon to maintain said first ring in sealing engagement with said recess, and said element when said solenoid is energized moving out of said opening as said armature moves to said second position to permit said liquid to discharge from said metering chamber through said first passage means due to the pressure on said liquid, said armature when said solenoid ceases to be energized returning to said first position due to the weight of said armature and the action of pressurized liquid on said armature as said liquid discharges into said metering chamber from said tubular valve seat, said first ring formed from a resilient material that is inert to said pressurized liquid said second end of said armature including said valve means having a greater area than the portion of said first end and element exposed to said pressurized liquid when said element is in said first position, with said armature due to the differential in areas on opposite ends thereof exposed to said pressurized liquid at all times tending to remain in said first position to seal with said first ring, and said armature only moving from said first position when said solenoid is energized to create a magnetic field.